Automatic curtain-roller.



E. DRNG.

AUTOMATIC CURTAIN ROLLER.

APPLICATION FILED SEPT. 27, 1909.

Patented May 17, 1910.

ANnaEw B. GRAHAM co. FNuTo-LHHQGMPNEFS. wAsu\Nu1on,o. c.

ERNST DRING, OF ZOSSEN, GERMANY.

AUTOMATIC CURTAIN-ROLLER.

Specification of Letters Patent.

Application filed September 27, 1909.

Serial No. 519,775.

This invention relates to an automatic` roller for curtains, blinds, awnings, maps and the like, the rolling or winding being effected under the action of a helical spring, which is tensioned during the unwinding movement and acts on a slidably but not rotatably mounted screw nut whereby the rotary movement of the winding roller in the winding direction is effected. This invention consists essentially in the feature that the screw nut, which is slidably mounted in the known manner by means of two lugs in the slots of a fixed sleeve and is subjected to the action of the yielding helical spring rotates a spindle extending through the nut and having a screw-thread of great pitch, such rotary movement being transmitted by gearing wheels to a winding roller mounted on the hub of one of the wheels. By means of this arrangement, the power of the tensioned spring alone is sulicient to automatically roll or wind the curtain without the assistance of cords.

Referring to the accompanying drawing, Figure l is a longitudinal section of the automatic roller and Fig. 2 a crosssection according to line A-B of Fig. l.

The roller a, which serves for raising and lowering the curtain, is secured on the hub of a toothed wheel ZJ, which is adapted to freely rotate on a xed sleeve c having two slots z' j. By the toothed wheel b and the gearing wheels Z e f, the rotary movement of the roller is transmitted to the spindle g arranged centrally in the interior of the sleeve c. The spindle has a screw thread with a great pitch engaging with a nut Z which engages by means of two lugs In in the slots z' y' of the sleeve c. A helical spring s surrounds the spindle g.

During the unwinding or lowering of the curtain eii'ected by a hand pulling movement and a corresponding rotation of the roller a, the rotary movement is transmitted to the spindle g by means of the toothed wheel b, on which the roller a is mounted. In consequence of this rotaryy movement, the nut Z, which is prevented from rotating owing to the engagement of its lugs Ze in the slots z j of the fixed sleeve c, is caused to make a sliding movement toward the left, whereupon the helical spring s is tensioned.

The tensioned helical spring s automatically rolls or winds the linen cloth as soon as the curtain is released from its stretched or partly stretched and secured position. The spring s then presses the nut Z toward the right, the latter rotates the spindle and the roller a by means of the toothed wheels f c Z and the toothed wheel Z) in the direction opposite to the aforesaid direction of rotation, whereby the winding or raising of the curtain takes place.

As indicated by dotted lines in Fig. l, a belt or cord pulley may be connected to one of the gear wheels for the purpose of unwinding or lowering the curtain.

In order that the blind or shade may be Patented May 17, 1910.

retained in its lowered position I provide upon the lower edge of such blind or shade an eyelet which is adapted to engage a stud or peg driven into a suitable part of the window easement, and when the eyelet and stud are in engagement the curtain is prevented from rolling up.

The ratio of pitch and resistance of the helical thread and the gearing may be such as to render it possible to adjust the roller automatically in any winding or Vraising position.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim and wish to secure by Letters Patent is:-

In a device of the character described, the combination with a xed sleeve provided with oppositely disposed longitudinally extending slots and a roller exterior thereto, of a threaded spindle revolubly mounted in said sleeve, a helical spring arranged about the spindle, gearing by means of which said spindle may be rotated through rotation of said roller, and a nut having lugs entering the slots in said sleeve, said nut being adapted for longitudinal but not rotary movement on said spindle, whereby when the roller is rotated to unwind the shade Carried thereby said nut tensions said helical spring and when the shade is released said nut permits the spring to unex and automatically rewind the shade on the roller.

In testimony whereof I have affixed my signature in presence of two Witnesses.

ERNST DRING.

Witnesses HENRY HASPER, WOLDEMAR HAUPT. 

